Based on the recommendations on this site, my hubby and I decided to leave Atlantic City NJ - where we're visiting and usually find lots of beach glass - to see what we could find an hour and a half away at Fortescue Beach, NJ...and all I have to say is WOW!
Over the course of an hour, at high tide(less than ideal conditions) we found the most ridiculous amount of nicely tumbled glass we have EVER found - and we've been to beaches all over MD, DE, NY and NJ.
I'd highly suggest visiting if you want a non-stop, super-successful trip.
It is a small, extremely quiet beach that is off the beaten path and relatively isolated, but I'm certain that even if people start visiting just for the glass, there will be PLENTY to go around :)
